An automated system for unattended repetitive sampling and analysis of volatile organic compounds has been designed and a prototype constructed. The sampling/analysis scheme involves reduced temperature preconcentration of analytes from whole air with subsequent thermal desorption and capillary column gas chromatographic analysis. This paper presents the hardware configuration, timing cycles and overall functional integration of the system. The compact sample collection/injection package is described and data are given to show temperature change rates and plateau stability for the various heated and cooled analytic zones. The system is based on modified commercially-available equipment and is ultimately intended for semi-real time monitoring from a manifold or as a centrally located laboratory instrument for analyzing air samples collected in the field.